1. Field of the Invention
This invention relates to a cutter apparatus for cutting rope into a plurality of cut fibers, and to a method of cutting. More particularly, the invention relates to an apparatus and method employing a plurality of spaced apart cutting blades in a substantially closed configuration, with the blades facing either inwardly or outwardly. In accordance with this invention, the blades are parallel to each other and are obliquely arranged with respect to a central plane dissecting all of the blades. The resulting cut fibers are preferably of staple lengths in the range of about 2 mm to 150 mm or even more or less.
2. Discussion of the Prior Art
Rope cutters have heretofore been provided which result in either the formation of fibers having approximately the same length, or fibers of varying lengths.
For instance, in U.S. Pat. No. 3,915,042 (Laird), of common assignment herewith, a cutter is provided for cutting rope into fibers of varying lengths. A plurality of blades are provided and have cutting edges which are arcuately arranged and face either inwardly or outwardly. Rope is then fed against the cutting edges of the blades forcing the rope against the cutting edges and through the spaces between them. The edges of the blades are angularly arranged with respect to each other to vary the distances between adjacent cutting edges along the lengths of adjacent blades so that when the rope is cut, the resulting cut fibers have varying lengths in proportion to the distance between the cutting edges at the point of cutting. As may be seen from review of this patent, all of the cutting edges are not parallel to one another.
A precision cutter is disclosed in U.S. Pat. No. 3,861,257 (Laird et al), of common assignment herewith, wherein the resulting fibers are all of uniform length. A plurality of blades are provided and have cutting edges which are arcuately arranged and face inwardly. Rope is fed within the curve and pressed against the edges of the blade, forcing the rope outwardly against the cutting edges. The bodies of the cutting blades diverge outwardly in the direction taken by the cut fibers and the cut fibers are conveyed by a fluid such as air to a collecting chamber or the like.
Other patents directed toward cutting apparatus and the like, include: U.S. Pat. Nos. 2,631,668 (Wicker); 3,485,120 (Keith); 3,557,648 (Coffin et al); 3,744,361 (Van Doorn et al); 3,768,355 (Farmer et al); 3,826,163 (Spaller, Jr. et al); 3,831,481 (Van Doorn et al); 3,948,127 (Vehling et al); and 4,063,479 (Roncato).
In those devices which are characterized by the provision of a plurality of parallel spaced blades which are perpendicular to a centrally disposed plane passing therethrough, the rope or tow mass which is to be cut thereby often bulges up behind the pressure wheel device causing extreme side pressure on the blades. This extreme pressure chips the fine edges of the blades, greatly reducing their life and in some cases, causes blade breakage. Also, in these prior art devices, when cutting fibers to relatively short lengths, the fibers tend to pack about the cutting edges, causing the cutter to jam. Furthermore, in certain instances, heat builds up in these devices due to frictional, and other factors, which heat tends to deform the fibers, if they are thermoplastic, so that small fiber crimps in the form of "V"s or the like are formed in the fibers as they attempt to pass through the agglomeration of fibers disposed about the blades.
Accordingly, there remains a need in the rope cutting art for the production of a rope cutting apparatus, which minimizes fiber agglomeration at the cutting blade locations. Of particular importance is the need for a rope cutter which can provide for cut fibers of two millimeters or less, wherein this agglomeration phenomenon does not occur.
In addition to the above, there is a need in the art for a cutting apparatus of the type which will not deform the cut fibers, which deformation often occurs when the fibers have difficulty passing through the spaces between adjacent blades.
Accordingly, it is an object of the present invention to provide a rope cutting mechanism wherein fiber agglomeration at the blade locations is minimized, thus resulting in longer blade life, reduced unwanted deformation of the fibers, and an over-all increase in production speed.
These and other objects and advantages of the invention will further appear hereinafter in conjunction with the drawings and following detailed description of the invention.